Endoscopic surgery frequently requires the application of hemostatic clips or the use of other instruments which can ligate, grab or rip for a variety of purposes. Several significant characteristics of such instruments need to be simplicity in construction, reliability in operation, as well as low cost. Components that come into contact with internal organs in the body must also be effectively sterilized. Alternatively, the construction needs to be sufficiently economical to allow disposability of contaminated components. The layout of the instrument needs to be such as to give the surgeon good feedback during the procedure as to allow as much control as possible while using the instrument. If component systems are used, it is important to have them securely attached to each other to avoid disconnection during the procedure which could jeopardize the patient's condition should detachment occur during a procedure.
Surgical instruments that are adaptable to more than one procedure are preferred. A versatile system of surgical instruments which allows different types of instruments to be used in conjunction with a given actuating system is also a desirable feature.
In the past, various surgical instruments have been developed which address some, but not all of these needs. Some of the problems in addressing many of these needs is that a solution to one of such needs works at cross purposes to another. The result in the past has been fairly complex instruments which have adequately addressed one or two of such design requirements while compromising on the others. Hemostatic clip applicators of varying complexity are known in the art as exemplified by U.S. Pat. Nos. 5,049,152; 5,084,057; 5,100,420; 5,163,945; 4,496,090; 3,675,688; and Reissue 28,932. Some of these patents reveal the use of a trigger grip to actuate a rod which motion is transferred directly to an operating component for accomplishing the purpose the instrument. Typical of such devices is U.S. Pat. No. 4,759,364 which illustrates pincers that are rod actuated. Yet, other clip appliers use a scissor grip and linkage in combination with spring forces to accomplish the clip application. U.S. Pat. No. 5,104,395 illustrates this principle. Other clip applicators that work in a similar fashion employ a ratcheted counterwheel, wherein, every time a clip is applied, the wheel is rotated giving a visual display to the surgeon of the number of clips remaining. This type of clip applier is shown in U.S. Pat. No. 5,047,038. Alternatively, to a ratcheted wheel indicating the number of clips remaining, transparent covers, such as shown in U.S. Pat. No. 5,104,395 have also been used to allow the surgeon to see how many clips remain in the stack.
Outside the medical field, staplers have been used to hold objects together, such as in upholstery construction. Typical of such staplers is U.S. Pat. No. 2,296,493 illustrating a hand-operated stapling machine using a rack and pinion linkage with regard to the staple feeding operation.
The apparatus of the present invention has the objectives of providing a simple and economical construction that gives good feedback in the surgeon's hand as to the procedure being conducted. A system of components is provided which has reusable and disposable features. The connection system between the components gives certainty of fixation, thereby eliminating the risk of accidental disconnection during a procedure within the body. The system also provides for adjustability for using clips of various lengths or widths. The clip applicator also provides a feature to ensure sufficient jaw opening prior to feeding of the next successive clip. This avoids the hazards of jamming.